Artificial Acousto-Magnetic Soft Microswimmers

Soft microswimmers capable of controlled motion at the microscale create new opportunities for particle manipulation, precise assembly of materials, targeted drug delivery, and noninvasive microsurgery. This study describes a hybrid microswimmer that uses a combination of acoustic and magnetic fields to demonstrate effective maneuverability. The soft microswimmer contains one or more microcavities at the center of its body and superparamagnetic particles within its polymer matrix. The microcavity supports an air bubble trap, which, when acoustically activated, produces a bubble oscillation that results in propulsion. The magnetic particles that are aligned in the form of chains ensure controlled motion in an external magnetic field. Utilizing both fields allows a swimmer to navigate at a relatively large propulsive force with precise maneuvering capabilities.